Fluid-driven bubble actuator arrays

ABSTRACT

This disclosure includes bubble actuator arrays and methods for making and using the same. Some bubble actuator arrays include a first flexible layer having a substantially flat first portion and a plurality of second portions that protrude away from the first portion to define chambers, a flexible second layer sealed to the first layer to define a plurality of cells in the chambers and between the layers, and where the array can be coupled to a fluid source such that the internal pressures of the cells can be varied. Some of the present methods include adjusting with a processor and fluid source the pressure in the cells of an array. Others of the present methods include placing sacrificial material into chambers of a molded first layer such that a plurality of cells is formed when a second layer is molded coincident to the first and the sacrificial material is removed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a national phase application under 35 U.S.C. § 371of International Application No. PCT/US2014/072338, filed Dec. 24, 2014,which claims the benefit of priority of U.S. Provisional PatentApplication No. 61/920,903, filed Dec. 26, 2013. The entire contents ofeach of the above-referenced disclosures are hereby incorporated byreference.

BACKGROUND

1. Field of Invention

The present invention relates generally to apparatuses and methods fordynamic control of surface morphology, and more specifically, but not byway of limitation, to two-dimensional fluid-driven bubble actuatorarrays.

2. Description of Related Art

Examples of fluid-driven actuator arrays are disclosed in U.S. Pat. No.6,092,249; and U.S. Pat. No. 5,267,365.

Devices that require contact with a user's body such as prostheticlimbs, beds, seat cushions, or helmets pose the risk for discomfort andsores, particularly when the user has limited mobility. In almost all ofthese devices, consistent conformal contact between the device and thehuman body is desirable for both comfort and safety.

With regards to prosthetic limbs, the volume of a residual limb changesthrough the gait cycle and throughout the day (Board, W. 2001; Sanders,Harrison et al. 2009). This may be particularly evident in transtibialamputations, as the tissue consistency from anterior to posterior isoften markedly different; however, this variation in tissue types existsin transfemoral amputations as well (Convery and Buis 1998). Residuallimb volume changes can result in excessive pressures, as well as shearand frictional forces upon a residual limb in a prosthesis socket. Ifconditions between a residual limb and prosthesis socket are suboptimal,discomfort, skin irritation, and/or pressure ulcers may result. Studieshave reported that among non-vascular transfemoral amputees one of themost frequent complaints is sore skin and/or irritation from prostheticlimb sockets. (Hagberg and Branemark 2001).

Current devices and methods designed to ensure fit and comfort forprostheses are generally passive. For example, some amputees placelayers of socks over their residual limb before insertion into aprosthesis socket in an attempt to achieve a better fit or to compensatefor residual limb volume changes. Additionally, certain systems may usevacuum-assisted prosthesis sockets, and others use air-cushionedsockets. Existing systems, however, are generally incapable ofmodulating or distributing the pressure exerted on the residual limb oractively compensating for residual limb volume changes.

Prosthetic limb users are not the only individuals susceptible tocontact related skin damage. Pressure ulcers may be caused by prolongedcontact between a bed or chair and a part of the body. Due to theirimmobility, stroke patients and individuals with spinal cord injuriesmay be particularly susceptible to such pressure ulcers.

Currently, safeguards against ulcers include frequent skin examination,body weight shifting, and monitoring of moisture accumulation.Additionally, certain cushions or water beds are available, but thesedevices still require outside human intervention to frequently move theindividual to avoid pressure ulcer formation. Existing methods may beinsufficient to prevent pressure ulcers because these methods are notcapable of actively modulating or distributing the pressure exerted onthe individual. Such existing methods may also require extensive humanresources.

Existing methods for impact protection may involve foam cushioningdisposed on and/or within a wearable device (e.g., protective gear, suchas, for example, helmets, pads, body armor, and/or the like). However,such existing methods may not ensure consistent conformal contactbetween the wearable device and a user of the wearable device (e.g.,existing crash helmets may be unable to ensure consistent conformalcontact between an inner surface of the helmet and a user's head and/ormay over pressurize some parts of the user's head). Furthermore, currentmethods may be unable to effectively distribute forces from an impact(e.g., whether spatially and/or temporally) to minimize damage to theuser.

Helmets may also be used for cranial remodeling of an infant skull.Plagiocephaly, an asymmetrical distortion of the skull, is a commoncondition in infants caused by both genetic malformities and externalfactors. One of the most effective treatments for correcting thisasymmetrical distortion is the use of an orthotic helmet. Orthotichelmets apply pressure to the non-deformed section of the head so thatthe skull grows in the appropriate direction, thereby rounding the head.Currently, the pressure exerted by an orthotic helmet generally cannotbe precisely determined. Frequent doctor visits (every one to four weeksfor a period of 3 to 6 months) and helmet reconfigurations are requiredfor proper treatment. Existing methods of cranial remodeling are notcapable of actively reshaping the skull as it grows or exerting knownpressures on the skull as prescribed by a doctor.

Robotic manipulators are typically used to grasp and move objects in anumber of degrees of freedom, and are used in a wide variety ofapplications, including, but not limited to, manufacturing, surgery,human/robot interactions, produce picking, and/or the like, and may beparticularly suited to applications in which human presence is dangerousand/or otherwise undesirable (e.g., space operations, working with toxicsubstances, and/or the like). The successful grasping and/or moving ofobjects can largely depend on the degree of conformal contact betweenthe object and the manipulator. For example, insufficient conformalcontact between the manipulator and the object can result in the objectbecoming separated from the manipulator during grasping and/or moving,and too strong of a conformal contact can cause damage to the object.Ensuring such adequate conformal contact typically requires precisemanipulator movements and/or manipulators specifically designed forinteraction with the particular object being manipulated. Depending onthe object, this can require the manipulator to be able to move inmultiple and complex degrees of freedom. Current robotic manipulatorsmay be capable of conforming to an object that is well-defined (e.g.,the material properties and/or shape of the object are known to therobotic manipulator and/or to the robotic manipulator controller).However, for undefined objects or objects that the manipulator has notbeen designed and/or configured to grasp, the grasping can besuboptimal, which may result in separation of the object from themanipulator and/or damage to the object.

Prosthetic manipulators can function similarly to robotic manipulators,and are typically either myoelectric or switch based. In either type,body movements such as muscle contractions can be used to actuate theprosthetic manipulator. As with robotic manipulators, successfulgrasping and/or movement of an object may require adequate conformalcontact between the manipulator and the object. Current prostheticmanipulators may not be capable of adequately grasping the wide varietyof objects a user may wish to interact with, and may require the user tochange or adjust the prosthesis. Additionally, fragile, slippery, orobjects that are otherwise difficult to grasp may require a degree ofprecision of manipulator control that current prosthetic manipulatorsare unable to provide.

SUMMARY

Some embodiments of the present apparatuses and methods use or include aflexible two-dimensional array of fluid-driven bubble actuators. In someembodiments, fluid can be injected into or removed from the bubbleactuators in order to cause the surface of the array to changetopography and/or stiffness (e.g., to distribute pressure loads and/orimpact loads, whether spatially and/or temporally, and/or provideconsistent conformal contact between an object such as a part of thehuman body and the bubble actuator arrays despite changing conditionssuch as volume changes of a residual limb). Thus, some embodiments ofthe present apparatuses and methods are configured to dynamicallymodulate the pressure exerted on an object in contact with the array.The surface of the bubble actuator arrays can be configured to varybased on sensor inputs or based on pre-programmed inputs and/orpassively, for example, based upon pressure and/or impact loads appliedto the bubble actuator arrays.

Some embodiments of the present apparatuses comprise: a flexible firstlayer comprising a substantially flat first portion and a plurality ofsecond portions each protruding away from the first portion to define achamber, a majority of which is surrounded by a boundary lying on thefirst portion; and a flexible second layer that is substantially flat;where the first layer is sealed in fixed relation to the second layeralong the boundaries to define a plurality of cells between the firstlayer and the second layer in the chambers and such that the first layerhas a surface overlying the cells; and the apparatus is configured to becoupled to a fluid source such that the fluid source can deliver fluidto vary internal pressures of the plurality of cells.

Some embodiments of the present apparatuses comprise: a flexible firstlayer comprising a first side that is substantially flat and a secondside having a substantially flat first portion and a plurality of secondportions each protruding inward toward the first side to define arecess, a majority of which is surrounded by a boundary lying on thefirst portion; and a flexible second layer; where the first layer issealed in fixed relation to the second layer along the boundaries todefine a plurality of cells between the first layer and the second layerin the recesses and such that a surface of either the first layer or thesecond layer overlies the cells; and where the apparatus is configuredto be coupled to a fluid source such that the fluid source can deliverfluid to vary internal pressures of the plurality of cells. In someembodiments, a surface of the first layer overlies at least some of theplurality of cells and a surface of the second layer overlies at leastsome of the plurality of cells.

In some embodiments of the present apparatuses, the first layercomprises a plurality of coupling members protruding from the firstportion opposite the second portions, the plurality of coupling membersembedded in the second layer. In some embodiments, the second layer ismolded around the coupling members of the first layer. In someembodiments, at least one of the first layer and the second layercomprises an elastic material. In some embodiments, at least a portionof at least one of the first layer or second layer has a thickness of0.25 millimeter (mm) or larger. In some embodiments, at least a portionof the surface is smooth such that cells underlying the smooth portionof the surface are configured to deflect the smooth portion of thesurface outwardly in at least a lateral and an axial direction under anincreased internal pressure of the cells underlying the smooth portionof the surface. In some embodiments, at least a portion of the surfaceis corrugated such that cells underlying the corrugated portion of thesurface are configured to deflect the corrugated portion of the surfaceoutwardly in a substantially axial direction under an increased internalpressure of the cells underlying the corrugated portion of the surface.In some embodiments, the apparatus is configured such that a maximumdisplacement of the surface overlying at least one of cells is between2% and 15% of a transverse dimension of the cell for each pound persquare inch (psi) increase in internal pressure between 1 psi and 5 psi.

Some embodiments of the present apparatuses are configured such that aninternal pressure in at least one of the plurality of cells can bevaried independently of an internal pressure in another one of theplurality of cells. In some embodiments, the apparatus is configuredsuch that an internal pressure in each of the plurality of cells can bevaried independently of an internal pressure in each of the others ofthe plurality of cells. In some embodiments, each of the plurality ofcells has a transverse dimension that is substantially equal to acorresponding transverse dimension of the others of the plurality ofcells.

In some embodiments of the present apparatuses, at least one of theplurality of cells has a transverse dimension that is different than acorresponding transverse dimension of another one of the plurality ofcells. In some embodiments, at least some of the plurality of cellssequentially decrease in size along at least one transverse direction ofthe flexible layers. In some embodiments, each of the plurality of cellshas a transverse dimension of 1 millimeter (mm) or larger. In someembodiments, each cell has a transverse dimension of between 5millimeters (mm) and 15 mm.

Some embodiments of the present apparatuses comprise a fluid sourceconfigured to be coupled to the layers and to vary internal pressures inthe plurality of cells.

Some embodiments of the present apparatuses comprise a plurality ofsensors coupled to the apparatus and configured to detect one or morephysical characteristics. In some embodiments, at least some of thesensors are configured to detect pressure. In some embodiments, at leastsome of the sensors are configured to detect shear-force. In someembodiments, at least some of the sensors are configured to detecttemperature. In some embodiments, at least some of the sensors areconfigured to detect pH. Some embodiments further comprise a processorconfigured to control the fluid source to adjust the internal pressurein the plurality of cells at least partly based on data detected by thesensors. Some embodiments further comprise: a memory configured to storepressure patterns; and a processor in communication with the memory andconfigured to control the fluid source to adjust the internal pressurein the plurality of cells at least partly based on the pressurepatterns.

Some embodiments of the present apparatuses are configured to be coupledto a prosthesis socket. In some embodiments, the apparatus is configuredto be coupled to a helmet. In some embodiments, the apparatus isconfigured to be coupled to a prosthetic limb. In some embodiments, theapparatus is configured to be coupled to a bed. In some embodiments, theapparatus is configured to be coupled to a seat.

Some embodiments of the present manipulators comprise at least twoopposing grasping members configured to move relative to one another tograsp an object; and one of the present apparatuses disposed on at leastone of the grasping members such that the apparatus (e.g., the firstlayer) will contact an object grasped between the grasping members(e.g., such that fluid can be delivered to the cells to expand the cellsand exert a force on the grasped object). In some embodiments, themanipulators further comprise a second one of the present apparatuses.In some embodiments, the first one of the present apparatuses isdisposed on a first one of the grasping members and the second one ofthe present apparatuses is disposed on a second one of the graspingmembers. In some embodiments, the internal pressures of the plurality ofcells of the first one of the present apparatuses can be variedindependently of the internal pressures of the plurality of cells of thesecond one of the present apparatuses.

Some embodiments of the present robotic grippers comprise one of thepresent manipulators.

Some embodiments of the present prosthetics (e.g., prosthetic hand,foot, arm, and/or leg, and/or the like) comprise one of the presentmanipulators. Some embodiments further comprise a socket configured toreceive a residual limb of a user; and one of the present apparatusesdisposed within the socket such that the apparatus will contact theresidual limb when the prosthetic arm is worn by the user.

Some embodiments of the present methods comprise: placing an amount ofpolymer material into a mold configured to form a flexible firstcomprising a plurality of recesses, each recess having a boundary thatsurrounds a majority of the recess and a mold configured to form aflexible second layer that is substantially flat; curing the polymermaterial; extracting a first layer and a second layer from the molds;and bonding the first layer to the second layer.

Some embodiments of the present methods comprise: placing a first amountof polymer material into a first mold piece; coupling a second moldpiece to the first mold piece to form a flexible first layer having asubstantially flat first portion and a plurality of second portions eachprotruding away from the first portion to define a chamber a majority ofwhich is surrounded by a boundary lying on the first portion; curing thefirst amount of polymer material; removing the second mold piece;placing a second amount of polymer material in the first mold piece;coupling a third mold piece to the first mold piece to form asubstantially flat second layer adjacent to the first layer andcomprising a plurality of fluid passageways; curing the second amount ofpolymer material; removing the third mold piece from the first moldpiece; and extracting the first layer and the second layer from thefirst mold piece. Some embodiments of the present methods comprise:placing a sacrificial material (e.g., gelatin, wax, and/or sugar) in thechambers of the flexible first layer; and removing, through theplurality of fluid passageways, the sacrificial material from thechambers.

Some embodiments of the present methods further comprise coating themolds with an anti-stiction agent. In some embodiments, theanti-stiction agent is parlyene. In some embodiments, the coating is1-10 μm thick.

In some embodiments of the present methods, the polymer materialcomprises RTV-4234-T4. In some embodiments of the present methods, thepolymer material comprises polyurethane rubber. In some embodiments ofthe present methods, the polymer material comprises natural rubber. Insome embodiments of the present methods, the polymer material comprisesnylon.

Some embodiments of the present methods comprise adjusting with aprocessor and fluid source an internal pressure of one or more of theplurality of cells in one of the present apparatuses. In someembodiments, the apparatus is in contact with a user.

The term “coupled” is defined as connected, although not necessarilydirectly, and not necessarily mechanically; two items that are “coupled”may be unitary with each other. The terms “a” and “an” are defined asone or more unless this disclosure explicitly requires otherwise. Theterm “substantially” is defined as largely but not necessarily whollywhat is specified (and includes what is specified; e.g., substantially90 degrees includes 90 degrees and substantially parallel includesparallel), as understood by a person of ordinary skill in the art. Inany disclosed embodiment, the terms “substantially,” “approximately,”and “about” may be substituted with “within [a percentage] of” what isspecified, where the percentage includes 0.1, 1, 5, and 10 percent.

Further, a device or system that is configured in a certain way isconfigured in at least that way, but it can also be configured in otherways than those specifically described.

The terms “comprise” (and any form of comprise, such as “comprises” and“comprising”), “have” (and any form of have, such as “has” and“having”), “include” (and any form of include, such as “includes” and“including”), and “contain” (and any form of contain, such as “contains”and “containing”) are open-ended linking verbs. As a result, anapparatus that “comprises,” “has,” “includes,” or “contains” one or moreelements possesses those one or more elements, but is not limited topossessing only those elements. Likewise, a method that “comprises,”“has,” “includes,” or “contains” one or more steps possesses those oneor more steps, but is not limited to possessing only those one or moresteps.

Any embodiment of any of the apparatuses, systems, and methods canconsist of or consist essentially of—rather thancomprise/include/contain/have—any of the described steps, elements,and/or features. Thus, in any of the claims, the term “consisting of” or“consisting essentially of” can be substituted for any of the open-endedlinking verbs recited above, in order to change the scope of a givenclaim from what it would otherwise be using the open-ended linking verb.

The feature or features of one embodiment may be applied to otherembodiments, even though not described or illustrated, unless expresslyprohibited by this disclosure or the nature of the embodiments.

Some details associated with the embodiments described above and othersare described below.

BRIEF DESCRIPTION OF THE DRAWINGS

The following drawings illustrate by way of example and not limitation.For the sake of brevity and clarity, every feature of a given structureis not always labeled in every figure in which that structure appears.Identical reference numbers do not necessarily indicate an identicalstructure. Rather, the same reference number may be used to indicate asimilar feature or a feature with similar functionality, as maynon-identical reference numbers. The figures are drawn to scale (unlessotherwise noted), meaning the sizes of the depicted elements areaccurate relative to each other for at least the embodiment depicted inthe figures.

FIG. 1A is a side cross-sectional view of one embodiment of the presentbubble actuator arrays.

FIG. 1B is a top perspective view of the embodiment of FIG. 1A.

FIG. 1C is a side cross-sectional view of a second embodiment of thepresent bubble actuator arrays.

FIG. 1D is a top perspective view of the embodiment of FIG. 1C.

FIG. 2A is a side cross-sectional view of a third embodiment of thepresent bubble actuator arrays.

FIG. 2B is a top perspective view of the embodiment of FIG. 2A.

FIG. 2C is a top perspective view of a fourth embodiment of the presentbubble actuator arrays.

FIG. 2D is a side cross-sectional view of the embodiment of FIG. 2C.

FIG. 3 is a graph showing surface displacement versus internal cellpressure for certain embodiments of the present bubble actuator arrays.

FIG. 4 is a side cross-sectional view of a fifth embodiment of thepresent bubble actuator arrays that includes a plurality of sensors.

FIG. 5 is a cutaway perspective view of a sixth embodiment of thepresent bubble actuator arrays that is configured to be coupled to aprosthesis socket.

FIG. 6 is a perspective view of a mask that comprises a seventhembodiment of the present bubble actuator arrays.

FIG. 7A is a perspective view of a helmet that comprises an eighthembodiment of the present bubble actuator arrays.

FIG. 7B is a perspective view of a helmet that comprises a ninthembodiment of the present bubble actuator arrays.

FIG. 8 is a cutaway side view of a bed or seat cushion that comprises atenth embodiment of the present bubble actuator arrays.

FIG. 9 is a side view of a manipulator that comprises an eleventhembodiment of the present bubble actuator arrays.

FIG. 10 is a flow chart of one embodiment of the present methods formaking an embodiment of the present bubble actuator arrays.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

FIG. 1A shows a cross-sectional view of an embodiment 10 of the presentbubble actuator arrays. In the embodiment shown, array 10 comprises afirst flexible layer 14 comprising a substantially flat first portion 14a and a plurality of second portions 14 b each protruding away from thefirst portion to define a chamber 16, a majority of which is surroundedby a boundary 18 lying on the first portion.

In the embodiment shown, array 10 further comprises a second flexiblelayer 20 that is substantially flat. In the embodiment shown, the firstlayer 14 is sealed in fixed relation to the second layer alongboundaries 18 to define a plurality of cells 22 between the first layerand the second layer in chambers 16 and such that the first layer has asurface 34 overlying the cells. In other embodiments, such as array 10b, shown in FIGS. 2A and 2B, and array 10 c, shown in FIGS. 2C and 2D,at least one of flexible layers (e.g., 14 c or 20) comprises a firstside that is substantially flat and a second side having a substantiallyflat first portion and a plurality of second portions each protrudinginward toward the first side to define a plurality of recesses 16 a,where each recess has a boundary 18 a that surrounds a majority of therecess. In these embodiments, the first layer is sealed in fixedrelation to the second layer along the boundaries to define a pluralityof cells 22 a between the first layer and the second layer in therecesses and such that a surface 34 a of the first layer or the secondlayer overlies the cells (e.g., layer 14 c in array 10 c has surface 34a which overlies cells 22 a). In such embodiments, the arrays comprise asubstantially flat surface 34 a when cells 22 a have an internalpressure (e.g., 42) of nearly ambient pressure (e.g., the cells have aninternal pressure substantially equal to the ambient pressure acting onthe outside of the cells). In other embodiments, a surface of the firstlayer can overlie at least some of the plurality of cells and/or asurface of the second layer can overlie at least some of the pluralityof cells (e.g., recesses 16 a can be located in either or both of thetwo flexible layers).

Cells (e.g., 22) of the present disclosure can comprise any suitableshape, such as, for example, a shape having a rounded (e.g., circular,elliptical, and/or the like), polygonal (e.g., triangular, rectangular,pentagonal, hexagonal, and/or the like), and/or the like transverseand/or longitudinal cross-section.

Referring back to FIGS. 1A and 1B, in the embodiment shown, the firstlayer 14 comprises a plurality of coupling members 28 protruding fromthe first portion 14 a opposite the second portions 14 b, the pluralityof coupling members embedded in the second layer 20. In the embodimentshown, the second layer is molded around the coupling members of thefirst layer. In other embodiments, the first layer can be sealed to thesecond layer in any manner which permits the functionality described inthis disclosure, including, but not limited to, through oxygen plasmaactivation, adhesive, melting, fasteners, and/or the like.

In the embodiment shown, array 10 comprises a plurality of fluidpassageways 30 in fluid communication with cells 22 such that fluid canbe delivered to or removed from cells 22 via passageways 30. The presentarrays can be used with any suitable fluid, such as, for example, air,water, Newtonian fluids, non-Newtonian fluids, and/or the like. In thisembodiment each cell has a dedicated passageway 30 such that fluid canbe delivered to or removed from each cell 22 individually. In otherembodiments, multiple cells 22 can be in fluid communication with eachother via passageways 30 such that fluid can be delivered to or removedfrom each of a plurality of groups (each including a plurality) of cells22 independently (e.g., array 10 c). In the embodiment shown, boundary18 is not interrupted for fluid passageways 30 which instead passthrough second layer 20; however, in other embodiments, boundary 18 maybe interrupted by fluid passageways passing between layers 14 and 20 butstill be continuous around a majority of the perimeter of each cell suchthat boundary 18 still defines each cell 22. In such embodiments, thepresent bubble actuator arrays can be configured to deflect surfaces(e.g., 34) of both first and second layers under applied internal cellpressures (e.g., 42).

In the embodiment shown, array 10 is configured to be coupled to a fluidsource 38, such that the fluid source can deliver fluid to vary internalpressures (e.g., positive internal pressure indicated by arrows 42) ofcells 22 (e.g., individually and/or collectively), such as by deliveringfluid to the cells through fluid passageways 30. In some embodiments,such as the one shown, each cell 22 is configured to be capable ofproducing a large surface deflection of surface 34 (e.g., in direction48 and/or direction 46 to an outwardly deflected position 50) and/or toapply a large force (e.g., in the direction indicated by arrow 46) to anobject in contact with surface 34 through pressurization (e.g., asindicated by arrows 42) of some or all of cells 22 and/or deformation ofthe surface 34 corresponding to the pressurized cells (e.g., indirection 48 and/or direction 46) caused by the delivery of fluid to thepressurized cells. In some embodiments, fluid can be moved between cells(e.g., 22) passively (e.g., without requiring operation of fluid source38). For example, in some embodiments, deformation of one cell may causefluid to communicate from the cell to one or more others of the cells,for example, via shared fluid passageway(s) 30 (e.g., and any given cellmay be interconnected with any number of other cells via any number ofshared fluid passageway(s)). Such passive fluid movement amongst thecells can be adjusted, for example, by varying the thickness (e.g., 62)of layers that at least partially define the cells, cell transversedimensions (e.g., 66), configuration of shared fluid passageways (e.g.,30), and/or the like. In these and similar embodiments, cells (e.g.,22), fluid passageways (e.g., 30), and/or the like may be filled with afluid. In some such embodiments, fluid source 38 may be omitted.

Some embodiments of the present apparatuses (e.g., actuators includingan embodiment of the present bubble actuator arrays) and systemscomprise a fluid source 38 that is configured to be coupled to the array(e.g., 10) (e.g., to cells 22 via fluid passageways 30) such that thefluid source can deliver fluid to and/or remove fluid from the cells tovary internal pressures (e.g., 42) in the cells. Unless otherwiseindicated by the context of its use, the term “pressure” includes, butis not limited to, positive pressures, negative (vacuum) pressures, andzero (ambient) pressures, all relative to an ambient (e.g., atmospheric)pressure.

In the embodiment shown, array 10 further comprises a processor 54 thatis configured to control fluid source 38 to adjust the internalpressures (e.g., 42) in the plurality of cells. In this embodiment,array 10 also comprises memory 58 in communication with processor 54,the memory configured to store information about actuation of fluidsource 38 and/or predefined pressure patterns for actuation of array 10(e.g., sequential pressurization of cells 22 individually or in groups).In some embodiments pressure patterns can include desired internalpressures (e.g., 42) in at least some of the plurality of cells (e.g., 5pounds per square inch (psi) of internal pressure in at least one cell).In some embodiments, pressure patterns can include desired measuredpressures between the surface (e.g., 34) and an object (e.g., 74), asdescribed in more detail below with reference to FIG. 4. In theseembodiments, the processor can be configured to control the fluid sourceto adjust the internal pressure in the plurality of cells at leastpartly based on the pressure patterns. Such components and features canfurther facilitate modulation of pressure levels at various points alongthe surface (e.g., 34). Unless otherwise indicated by the context of itsuse, the terms “a processor” or “the processor” mean one or moreprocessors and may include multiple processors configured to worktogether to perform a function.

In some embodiments, at least one of the first layer and the secondlayer comprises an elastic material. For example, in the embodimentshown, first layer 14 comprises an elastic material (e.g., rubber,polymer, silicone, and/or the like) such that the first layer candeflect when cells 22 are pressurized and surface 34 can expandelastically (e.g., to a position 50) and return to the pre-expandedstate when cells 22 are depressurized. In some embodiments, at least aportion of at least one of the first layer or second layer has athickness 62 of 0.25 millimeter (mm) or larger (e.g., greater than anyone of, or between any two of: 0.25, 0.5, 1, 1.5, 2, 5, 10, 15, 25,and/or 50 mm). In some embodiments, at least a portion of at least oneof the first layer or second layer has a thickness 62 of between 0.25 mmand 50 mm. For example, in the embodiment shown, the first layer 14 hasa thickness 62 of between 0.5 mm and 1.5 mm. Through selection of layerthickness 62, finer control can be had over surface stiffness and/ortopography under desired ranges of applied internal cell pressures(e.g., 42) for particular implementations of the present arrays. Forexample, increases in first layer thickness may increase first layerstiffness and thereby decrease deflection of surface 34 for a giveninternal cell pressure.

In the embodiment shown, at least a portion of the surface is smoothsuch that cells underlying the smooth portion of the surface 35 (e.g.,cell 22 g) are configured to deflect the smooth portion of the surface35 outwardly in at least a lateral direction (e.g., 48) and an axialdirection (e.g., 46) under an increased internal pressure (e.g., 42) ofthe cells underlying the smooth portion of the surface (e.g., for aresulting smooth surface 35 displacement 50). In other embodiments, suchas array 10 a shown in FIGS. 1C and 1D, at least a portion of thesurface is corrugated, such that cells underlying the corrugated portionof the surface 36 (e.g., cell 22 h) are configured to deflect thecorrugated portion 36 of the surface outwardly in a substantially axialdirection (e.g., the direction indicated by arrow 46) under an increasedinternal pressure (e.g., 42) of the cells underlying the corrugatedportion of the surface (e.g., for a resulting corrugated surface 36displacement 50 a). Such features of the surface 34 can be selectedand/or configured to affect the performance of the present bubbleactuator arrays.

Referring back to FIGS. 1A and 1B, in the embodiment shown, each ofcells 22 has a transverse dimension 66 of 1 millimeter (mm) or larger(e.g., greater than any one of, or between any two of: 0.25, 0.5, 1,1.5, 2, 5, 10, 15, 25, 50, 75, 100, 150, 200, 250, 300, and/or 350 mm),such as, for example, between 1.5 mm and 15 mm. In some embodiments,each of cells 22 has a transverse dimension 66 of 50 mm or smaller. Inthe embodiment shown, each of cells 22 has a transverse dimension 66that is substantially equal to a corresponding transverse dimension ofthe others of the plurality of cells: cells 22 are substantially thesame size. In other embodiments, at least one of the plurality of cells22 has a transverse dimension 66 that is different than a correspondingtransverse dimension of another one of the plurality of cells (e.g.,array 10 c). Cells (e.g., 22) of the present disclosure can have anysuitable height (e.g., 68) (e.g., which may be measured when an internalpressure of the cell is substantially equal to an ambient pressure),such as, for example, greater than any one of, or between any two of:0.25, 0.5, 1, 1.5, 2, 5, 10, 15, 25, 50, 75, 100, 150, 200, 250, 300,and/or 350 mm.

FIGS. 2C and 2D depict a fourth embodiment 10 c of the present bubbleactuator arrays. Array 10 c is substantially similar to array 10 b withthe primary exception that the cells (22 a, 22 b, 22 c, 22 d, and 22 e)of array 10 c have different sizes, and fluid passageways 30 a of array10 c are configured such that groups of cells (e.g., cells 22 a, 22 b,22 c, 22 d, and 22 e) are in fluid communication with each other suchthat fluid can be delivered to and/or removed from groups of cells (eachgroup including a plurality of cells). In this embodiment, an internalpressure (e.g., 42) in at least one of the plurality of cells 22 can bevaried independently of an internal pressure in another one of theplurality of cells (e.g., via fluid passageways 30 a coupling at leasttwo cells 22 together). In other embodiments, such as array 10 depictedin FIGS. 1A and 1B, the present bubble actuator arrays are configuredsuch that an internal pressure in each of the plurality of cells can bevaried independently of an internal pressure in each of the others ofthe plurality of cells (e.g., through a dedicated fluid passageway 30for each cell 22).

In some embodiments, at least some of the plurality of cellssequentially decrease in size along at least one transverse direction.For example, in the embodiment shown, the cells decrease in size indirection 70. In particular, cells 22 b are smaller than cells 22 a,cells 22 c are smaller than cells 22 b, cells 22 d are smaller thancells 22 c, and cells 22 e are smaller than cells 22 d. As with array 10b, the cells of array 10 c have a transverse dimension (e.g., diameter)of 50 mm or smaller. In the embodiment shown, cells 22 a have a diameterof 10 mm, cells 22 b have a diameter of 8 mm, cells 22 c have a diameterof 6 mm, cells 22 d have a diameter of 4 mm, and cells 22 e have adiameter of 2 mm (e.g., each cell 22 of array 10 c has a transversedimension of between 5 mm and 15 mm, and larger than 1 mm).

FIG. 3 shows a graph of surface displacement (e.g., deflection 50measured in direction 46, as illustrated in FIG. 1A) relative tointernal cell pressure (e.g., 42) for a first layer thickness 62 of 1mm. For this graph, the cells (e.g., 22) have circular shapes andtransverse dimensions (diameters) 66 of 6 mm, 8 mm, and 10 mmrespectively. As shown, variations in cell transverse dimension canaffect surface displacement of the cell surface for given internal cellpressures (e.g., 42). As indicated in the graph, some embodiments of thepresent bubble actuator arrays are configured such that the displacementof the plurality of cells (e.g., each of the plurality of cells 22) canbe governed by at least the internal pressure (e.g., 42), the transversedimension (e.g., 66), and/or the layer thickness (e.g., 62). Forexample, for the embodiments represented in FIG. 3, a maximum surfacedisplacement for each of the plurality of cells (e.g., 22) is between 2%and 15% of transverse dimension (e.g., 66) of the cell for each poundper square inch (psi) increase in internal pressure (e.g., 42) between 1psi and 5 psi. Other embodiments of the present bubble actuator arrayscan be configured such that a maximum surface displacement for each ofthe plurality of cells (e.g., 22) is as large as 50 mm under internalpressures (e.g., 42) as high as 50 psi. Through selection of suchcomponents and features, embodiments of bubble actuator arrays can beconfigured to obtain a desired range of surface (e.g., 34)displacements. For example, layer thickness, cell size, and/or cellshape can be selected (e.g., based on clinical data and/or desiredperformance characteristics) for a given application. As a furtherexample, in some embodiments (e.g., array 10 c), cells of differentsizes can be in communication with each other such that a commonpressure level produces varying deflections for different ones of thecells.

FIG. 4 depicts a fifth embodiment 10 d of the present bubble actuatorarrays. Array 10 d is substantially similar to array 10, with theprimary exception that array 10 d further comprises a plurality ofsensors 78 coupled to array 10 that are be configured to detect one ormore physical characteristics. In some embodiments, for example, thephysical characteristic(s) that the sensors are configured to detect canbe indicative of conditions between surface 34 and an object 74 incontact with a surface (e.g., a person). Sensors 78 can, for example, beconfigured to detect one or more of pressure, shear-force, temperature,pH, and/or other characteristics. Various suitable sensors arecommercially available from a variety of sources, such as, Tekscan,Inc., Vishay Precision Group, Inc., and/or Interlink Electronics. In theembodiment shown, sensors 78 are coupled to a flexible polymericsubstrate 82. In other embodiments, sensors 78 may be disposed at anysuitable location, such as, for example, coupled directly to surface 34(without substrate 82), disposed such that the bubble actuator array(e.g., or cells 22 thereof) lies between sensors 78 and an object 74(e.g., coupled to second flexible layer 20), disposed within fluidpassageway(s) 30, and/or the like. While not additionally shown in FIG.4, as with array 10, array 10 d can be coupled to and/or comprise afluid source 38, a processor 54, and/or memory 58. In such embodiments,processor 54 can be configured to control fluid source 38 to adjust theinternal pressure (e.g., 42) in the plurality of cells 22 at leastpartly based on data detected by sensors 78. In such embodiments, array10 d can operate as a closed-loop system in which:

-   -   processor 54 autonomously monitors the pressure and shear-forces        between an object (e.g., 74) and surface 34 in real-time (e.g.,        via sensors 78) and    -   adjusts the pressure and shear forces by changing the internal        pressure of the cells (e.g., until data detected by sensors 78        corresponds to pressure patterns stored in memory 58).        This functionality can facilitate compensation for changing        conditions between an object (e.g., 74) and the surface 34. In        this embodiment, pressure patterns (as described generally above        with reference to FIG. 1A) can include desired measured        pressures between surface 34 and an object (e.g., 74), such as        may be measured by sensors 78 (e.g., 5 psi of pressure between        the surface and an object as measured by at least one sensor).        Pressure patterns can also include threshold values        corresponding to at least one location (e.g., no more than 20        psi of pressure between the surface and an object as measured by        at least one sensor). In other embodiments, the processor may        adjust the pressure and shear forces exerted by surface 34 on an        object 74 to account for moisture accumulation, pH, and/or the        like (e.g., a location between the surface and a human body with        excessive moisture may require less pressure than dry locations        to avoid discomfort and/or sore formation).

In some embodiments, the present bubble actuator arrays (e.g., surface34) can be configured to be coupled to a device that, in use, contacts auser's body. For example, FIG. 5 depicts a perspective view of aprosthetic socket liner 100 comprising a sixth embodiment 10 e of thepresent bubble actuator arrays. Array 10 e is substantially similar toarray 10 d with the primary exception that array 10 e is coupled (e.g.,through fasteners, adhesive, and/or the like) and contoured to aninterior surface of prosthetic socket liner 100 such that array 10 e canbe actuated to adjust the interface between a prosthetic socket and auser's residual limb (e.g., to precisely control the pressure exerted oneach portion of a user's residual limb contacted by liner 100). In someembodiments, a prosthetic socket or a prosthetic socket liner (e.g.,100) may be configured to be coupled to a source of vacuum (e.g., whichmay be the same as or different than a fluid source 38) (e.g., toenhance the fit of the prosthetic socket, prosthetic socket liner and/orthe like on the user's residual limb).

As with array 10 d, in the embodiment shown, array 10 e includes aplurality of sensors 78 coupled to surface 34 b and configured to detectone or more physical characteristics to facilitate monitoring andcontrolling the pressure and shear-forces of the prosthetic socketenvironment in real-time. For example, sensors 78 can be configured torecord data indicative of the conditions between the residual limb of auser and the prosthetic socket. This data can be communicated to aprocessor (e.g., 54), which can be further configured to adjust thestiffness and/or contour of the surface 34 b through the operation of acontrollable fluid source (e.g., 38) that is coupled to cells 22 f. Suchembodiments can compensate for pressure changes in the socketenvironment (e.g., due to ambulation and volume changes of a residuallimb) to at least ensure an adequate fit and/or decrease shear andfrictional forces on the skin of a residual limb, thus reducing the riskof skin irritation or sores. In the embodiment shown, cells 22 f arering-shaped, for example, liner 100 is a cup-shaped liner with an openproximal end 108 and a closed distal end 112 which defines an interiorvolume 116, where first flexible layer 14 d (substantially similar tolayer 14 in embodiment 10) is sealed to second flexible layer 20 c atboundaries 18 c to define a plurality of ring-shaped cells 22 f betweenthe first layer and the second layer and around volume 116.

FIG. 6 depicts a perspective view of a mask 200 comprising a seventhembodiment 10 f of the present bubble actuator arrays. Array 10 f issubstantially similar to array 10 d with the primary exception thatarray 10 f is coupled (e.g., through fasteners, adhesive, and/or thelike) and contoured to an interior surface of mask 200 such that array10 f can be actuated to adjust the interface between mask 200 and auser's face (e.g., to precisely control the pressure exerted on eachportion of a user's face contacted by mask 200). As described above forarray 10 e, array 10 f can be configured with sensors (e.g., 78) and aprocessor (e.g., 54) to be capable of operating in a closed-loop processto ensure intimate contact between mask 200 and a user's face. Forexample, the sensors can be configured to monitor the pressure exertedon different contacted parts of the user's face by mask 200. A targetedsurface pressure value can be maintained by a processor (e.g., 54) byvarying the internal pressures (e.g., 42) in cells 22, and thus thedeflections (e.g., 50), of a plurality of cells (e.g., 22) throughcontrol of a fluid source (e.g., 38) coupled to the plurality of cells(e.g., through fluid passageways 30). This embodiment is thus configuredand can be used to ensure conformal contact between a user's face (e.g.,to ensure consistent pressure across a skin graft for a patient withsevere facial burns).

FIG. 7A depicts a helmet 300 (e.g., a helmet to be worn during asporting activity or an orthotic helmet) comprising an eighth embodiment10 g of the present bubble actuator arrays. Array 10 g is substantiallysimilar to array 10 d with the primary exception that array 10 g iscoupled (e.g., through fasteners, adhesive, and/or the like) andcontoured to an interior surface of helmet 300 such that array 10 g canbe actuated to adjust the interface between the helmet and a wearershead and thereby encourage conformal contact between the head and thehelmet regardless of the shape or contour of the user's head, as well asdistribute forces in stages in the event of impact in order to minimizedamage to the head. In embodiments in which helmet 300 is an orthotichelmet, array 10 g can facilitate application of known pressures toportions of the head of an infant as prescribed by a doctor (e.g.,through pressure patterns stored in memory 58) to re-shape the skull. Insome embodiments, the pressure exerted by array 10 g can be dynamicallyadjusted as the skull changes shape without having to change orreconfigure the orthotic helmet.

FIG. 7B depicts a helmet 300 comprising a ninth embodiment 10 h of thepresent bubble actuator arrays. Array 10 h is substantially similar toarray 10 g, with certain exceptions described below. As described above,in some embodiments of the present arrays (e.g., 10 h), fluid can bemoved between cells (e.g., 22) passively (e.g., without requiringoperation of a fluid source 38) (e.g., deformation of one cell may causefluid to communicate from the cell to another one of the cells, forexample, via a shared fluid passageway 30). For example, in thisembodiment, cells 22 i, 22 j, and 22 k share (e.g., are in fluidcommunication with one another via) a fluid passageway 30, such that,for example, deformation of cell 22 i may cause fluid to communicatefrom cell 22 i and to cells 22 j and/or 22 k.

Such passive fluid movement amongst the cells can be adjusted, forexample, by varying the thickness (e.g., 62) of layers that at leastpartially define the cells, cell transverse dimensions (e.g., 66), cellheights (e.g., 68), configuration of shared fluid passageways (e.g.,30), and/or the like. For example, in this embodiment, cell 22 i has acell height 68 that is larger than a cell height of cell 22 j or cell 22k. In this way, for example, in the event of an impact, a user's headwithin helmet 300 may deform cell 22 i before and/or to a larger degreethan cells 22 j and 22 k, which may cause pressurization of cells 22 jand 22 k (e.g., via fluid communication from cell 22 i via fluidpassageway 30) (e.g., progressively transmitting (e.g., in stages)and/or redirecting an impact to the user's head, thus reducing amagnitude of impact force experienced by the user). In array 10 h andsimilar arrays, fluid source 38, processor 54, memory 58, sensor(s) 78,and/or the like may be omitted.

FIG. 8 is a cutaway side view of a bed or seat 126 that comprises atenth embodiment 10 i of the present bubble actuator arrays. In thisembodiment, array 10 i is depicted as coupled to bed or seat 126;however, array 10 i or a similar array may be coupled to any suitablesupportive structure, such as, for example, a pillow, and/or the like.Array 10 i is substantially similar to array 10 d with the primaryexception that array 10 i is coupled and contoured to an outer surfaceof bed or seat cushion 126 (e.g., by setting array 10 i on a bed or seatcushion and/or securing array 10 i relative to the bed or seat cushion,such as, for example, with hook-and-loop fasteners and/or one or morestraps) such that array 10 i can be actuated to adjust the interfacebetween the bed or seat cushion 126 and a user (e.g., to preciselycontrol the pressure exerted on each portion of a user's body contactedby bed or seat cushion 126). In these and similar embodiments, a covermay be coupled to the array (e.g., comprising a clothing-like material,such as, for example, nylon, cotton, polyester, and/or the like) (e.g.,to enhance user comfort).

In these embodiments, bed or seat cushion 126 can further compriselinear displacement tile structures 130 disposed beneath cushion padding134 to provide for large changes to the pressure exerted on a user bythe bed or seat cushion and/or the stiffness and/or the contour of thesurface of bed or seat cushion 126. In these embodiments, the bubbleactuator arrays (e.g., 10 i) may thus be used for fine control overpressure patterns and/or conditions between a user and the bed or seatcushion. As described above for array 10 d, array 10 i can be configuredwith sensors (e.g., 78) and a processor (e.g., 54) to be capable ofoperating in a closed-loop process to ensure desired contact between bedor seat cushion 126 and a user. For example, the sensors can beconfigured to monitor the pressure exerted on different contacted partsof the user's body by bed or seat cushion 126. A targeted surfacepressure value can be maintained by a processor (e.g., 54) by varyingthe internal pressures (e.g., 42) in cells 22, and thus the deflections(e.g., 50), of a plurality of cells (e.g., 22) through control of afluid source (e.g., 38) coupled to the plurality of cells (e.g., throughfluid passageways 30). This embodiment is thus configured and can beused to ensure safe magnitudes, durations, and/or conditions of contactbetween a user's body and the bed or seat cushion (e.g., to protectagainst pressure ulcer formation), and thereby control the pressureexerted by bed or seat cushion on a user.

In these and similar embodiments, cell (e.g., 22) size, shape, and/orthe like may be tailored to a specific application. By way ofillustration, arrays (e.g., 10 i) configured for use in automobile,aircraft, and/or the like seats may comprise cells 22 having transversedimensions 66 ranging from 25 mm to 153 mm, with heights 68 ranging from38 mm to 127 mm, arrays configured for use in seat cushions (e.g.,office and/or home furniture cushions, and/or the like) may comprisecells 22 having transverse dimensions 66 ranging from 25 mm to 153 mm,with heights 68 ranging from 38 mm to 127 mm, arrays configured for usein mattresses, mattress pads, and/or the like may comprise cells 22having transverse dimensions 66 ranging from 50 mm to 254 mm, withheights 68 ranging from 25 mm to 305 mm, arrays configured for use inpillows and/or the like may comprise cells 22 having transversedimensions 66 ranging from 25 mm to 153 mm, with heights 68 ranging from50 mm to 204 mm, and/or the like. In some embodiments, the presentarrays may be configured such that air can flow past an exterior ofcells 22 (e.g., to provide for humidity and temperature control).

FIG. 9 is a side view of a manipulator that comprises a tenth embodimentof the present bubble actuator arrays. In the embodiment shown,manipulator 138 comprises at least two opposing grasping members 142 and146 (e.g., grasping members 142 and 146 are disposed on substantiallyopposite sides of manipulator 138). In the embodiment shown, thegrasping members are configured to move relative to one another to graspan object (e.g., 150) (e.g., the relative movement of grasping membersis generally indicated by arrows 148). Such movement can be accomplishedwith one or more actuators (not expressly shown), for example, linearactuator(s), screw-type actuator(s), pneumatic actuator(s), hydraulicactuator(s), and/or the like, and may be controlled and/or monitored bya processor (e.g., which may be the same as or in addition to theprocessor that can control actuation of array 10 j, described in moredetail below). In the embodiment shown, both grasping members 142 and146 are configured to move, however, in other embodiments, only onegrasping member may be configured to move in order to achieve relativemovement between the grasping members. In the embodiment shown, graspingmembers 142 and 146 comprise segments (e.g., 142 a, 142 b, 142 c, 146 a,and 146 b) that are configured to cooperate to facilitate relativemovement of the grasping members (e.g., each segment can pivot about ajoint 154 to effectuate relative movement of grasping members 142 and146 generally indicated by arrows 148). In other embodiments, thegrasping members can comprise any number of segments (e.g., may compriseonly one segment each).

In other embodiments, the relative motion between the grasping memberscan be accomplished through any different and/or additional structurethat permits the functionality described in this disclosure. Forexample, and not by way of limitation, the grasping members and/orsegments may move relative to one another in a translational degree offreedom (e.g., similar to a traditional screw-type clamp) instead of orin addition to a rotational degree of freedom (e.g., through pivotingabout joints 154, as described above). In yet other embodiments, thegrasping members may not be configured to move relative to one another,and grasping operation of the manipulator can be accomplished solelythrough actuation of bubble actuator array(s) 10 j, which are describedin more detail below.

In the embodiment shown, manipulator 138 comprises an eleventhembodiment 10 j of the present bubble actuator arrays or apparatuses. Inthe embodiment shown, array 10 j is substantially similar to array 10 d,with the primary exception that array 10 j is disposed on and contouredto an outer surface of a grasping member (e.g., 142 and/or 146) ofmanipulator 138 (e.g., array 10 j is overlaid onto grasping member(s) ofmanipulator 138 and can function as an “active skin” of the graspingmembers). In the embodiment shown, an actuator array 10 j is disposed oneach segment (e.g., 142 a, 142 b, 142 c, 146 a, and 146 b) of eachgrasping member (e.g., as shown, manipulator 138 comprises at least afirst array 10 j disposed on grasping member 142 and a second array 10j, different from the first array, disposed on grasping member 146).However, in other embodiments, any number of arrays can be disposed onany number of grasping members that permits the functionality describedin this disclosure (e.g., 1, 2, 3, 4, 5, or more arrays disposed on 1,2, 3, 4, 5, or more grasping members). For example, in some embodiments,the present manipulators can comprise a single array 10 j that can bedisposed on and/or across multiple grasping members (e.g., disposed ongrasping members 142 and 146 such that the array is contoured around theopening defined by and between the grasping members).

In embodiments of the present manipulators comprising more than onearray (e.g., 138), the arrays can be configured such that the internalpressures of the plurality of cells of at least one array can be variedindependently of the internal pressures of the plurality of cells ofother arrays (e.g., through configuration of fluid passageways 30,programming of processor 54, and/or connection to separate fluid sources38). In the embodiment shown, arrays 10 j are disposed on graspingmembers 142 and 146 such that at least one array will contact an object(e.g., 150) grasped between the grasping members (e.g., as shown).Through such contact, array(s) 10 j can be actuated to adjust theinterface between grasping members 142 and 146 and a grasped object(e.g., 150). As described above for array 10 d, array 10 j can beconfigured with sensors (e.g., 78) and a processor (e.g., 54) to becapable of operating in a closed-loop process to ensure desired contact(e.g., conformal contact) between grasping members and a grasped object(e.g., 150). For example, the sensors can be configured to monitor thepressure exerted on contacted portions of the grasped object.

In some embodiments, a targeted surface pressure value (e.g., from eachsensor) can be maintained by a processor (e.g., 54) by varying theinternal pressures (e.g., 42) in cells 22, and thus the pressure exertedby each cell, through control of a fluid source (e.g., 38) coupled tothe plurality of cells (e.g., through fluid passageways 30). Throughsuch actuation, pressure between the grasped object and the graspingmembers can be distributed to prevent over pressuring portions of thegrasped object which may cause damage to the object. Such embodimentsare thus configured to, and can be used to, precisely control thepressure exerted on a grasped object and/or ensure conformal contactbetween the grasped object and the grasping members. If conditionsbetween the grasped object and the grasping members change (e.g., theobject slips, deforms, and/or is otherwise displaced), the cells of thearrays can be dynamically pressurized and/or depressurized to maintainand/or regain conformal contact with the grasped object. In embodimentswith grasping members that are configured to move relative to oneanother (e.g., 138), the grasping members can be actuated to providecoarse adjustment of the interface between the grasped object and thegrasping members (e.g., grasping members can be moved relative to oneanother until an array 10 j detects, via sensors 78, a certain pressureand/or contact between the grasped object and the grasping members, forexample, during grasping), and/or array 10 j can be actuated to providefine control over pressure patterns and/or conditions between thegrasping members and the grasped object. Through actuation of arrays 10j of manipulator 138, precise control over the grasped object can beexercised without adding additional degrees of freedom to themanipulator (e.g., additional segments, joints, and/or the like). Suchfine adjustment provided by array(s) 10 j can also reduce the level ofprecision required in object locating (e.g., the manipulator can begenerally positioned near an object to be grasped and the array(s) canbe actuated to accomplish grasping operation).

Embodiments of the present manipulators can be used in wide range ofapplications, and may be particularly suited for applications thatrequire safety and controlled pressure loading (e.g., for graspingsensitive objects). For example, the present manipulators can be used inrobotic gripper arms for applications including, but not limited to,manufacturing, surgery, space operations, fruit and/or vegetable pickingand/or handling, human robot interactions, and/or the like. The presentmanipulators can also be configured for use with prosthetic limbs, forexample, to allow a user to handle objects of various size, shape,and/or fragility. Prosthetic limbs (e.g., prosthetic arms) whichcomprise an embodiment of the present manipulators (e.g., 138) mayfurther comprise a socket with one of the present bubble actuator arraysdisposed therein to control the conditions between a residual limb andthe prosthetic socket (e.g., socket 100, described above).

Some embodiments of the present methods comprise placing an amount ofpolymer material into a mold configured to form a flexible first layercomprising a plurality of recesses, each recess having a boundary thatsurrounds a majority of the recess (e.g., layer 14 c) and a moldconfigured to form a flexible second layer that is substantially flat(e.g., layer 20), curing the polymer material, extracting a first layerand a second layer from the molds; and bonding the first layer to thesecond layer. The extracted top and bottom layers can be bonded togetherby any means which permit the functionality described in thisdisclosure, including, but not limited to, through oxygen plasmaactivation, adhesive, fasteners, melting, and/or use of coupling membersdisposed on the layers (as described above with reference to FIG. 1A).

FIG. 10 shows a flow chart of one embodiment of the present methods. Inthe embodiment shown, the method comprises placing a first amount ofpolymer material 194 into a first mold piece 198 (166), coupling asecond mold piece 202 to the first mold piece to form a flexible firstlayer having a substantially flat portion and a plurality of secondportions each protruding away from the first portion to define a chambera majority of which is surrounded by a boundary lying on the firstportion (e.g., layer 14) (170), and curing the first amount of polymermaterial (cured first layer (e.g., 14) shown at 174). In this way, thefirst layer of the bubble actuator arrays (e.g., layer 14) can be moldedfirst. At step 178, the embodiment shown comprises removing the secondmold piece 202 and placing a sacrificial material 206 in the chambers ofthe first flexible layer (178), placing a second amount of polymermaterial 210 in the first mold piece (182), coupling a third mold piece214 to the first mold piece to form a substantially flat second layeradjacent to the first layer (e.g., an over-molding process) andcomprising a plurality of fluid passageways (e.g., layer 20) (186),extracting the first layer and the second layer from the first piece andremoving the sacrificial material from the chambers through the fluidpassageways (190) (e.g., to create a sealed first layer 14 and secondlayer 18 as shown in FIG. 1A). In some embodiments of the presentmethods, the sacrificial material may be removed from the chambersthrough the fluid passageways by melting, washing, squeezing, and/or thelike. In some embodiments, the sacrificial material comprises gelatin,wax, and/or sugar. However, in other embodiments, any sacrificialmaterial can be used which permits the functionality described in thisdisclosure (e.g., any material that will prevent the chambers of thefirst layer from filling with the second amount of polymer material atstep 210, and that can later be removed at step 190). In someembodiments of the present methods, a sacrificial material may not berequired (e.g., and the function of such a sacrificial material may beperformed by third mold piece 214).

In these embodiments, the array layers can be fabricated throughcompression molding (e.g., pressing the mold pieces together with thepolymer material disposed within the mold pieces) and/or injectionmolding (e.g., placing the mold pieces together before injecting thelayer material into the mold). In some embodiments of the presentmethods, the molds can be fabricated with a three-dimensional (3D)printer, for example, the Viper SLA 3D printer. In these embodiments,the molds can comprise a resin, for example, Accura 25 resin. In otherembodiments, the molds may be created through conventional machining andmolding processes, for example, constructed out of any suitable material(e.g., aluminum) on a computer numerical control (CNC) or manuallyoperated mill. In some embodiments of the present methods, the mold(s)are coated with an (e.g., sprayable) anti-stiction agent beforereceiving the polymer material. In further embodiments, theanti-stiction agent is parlyene, and in yet further embodiments, thecoating is 1-10 micrometers (μm) thick (e.g., 3 μm thick).

Furthermore, in some embodiments of the present methods, the polymermaterial comprises RTV-4234-T4, provided by Dow Corning under the nameXIAMETER, comprising a two component (base and curing agent) thermallycurable silicone. In other embodiments, the polymer material cancomprise liquid silicone rubber, polyurethane rubber, urethane rubber,natural rubber, polyurethane, nylon, and/or the like. In yet otherembodiments, the molds may be formed of a material that allows UV lightto reach the polymer material within the mold (e.g., constructed oftranslucent materials, such as acrylic), and the polymer material maycomprise a photosensitive polymer (e.g., such that the polymer materialmay be cured, at least in part, through exposure to UV light).

Other methods of the present disclosure comprise adjusting with aprocessor (e.g., 54) and fluid source (e.g., 38) an internal pressure(e.g., 42) of one or more of the plurality of cells (e.g., 22) in abubble actuator array (e.g., arrays 10, 10 a, 10 b, 10 c, 10 d, 10 e, 10f, 10 g, 10 h, 10 i, 10 j). In further embodiments, the bubble actuatorarray is in contact with a user (e.g., the user as object 74 in FIG. 4).

The above specification and examples provide a complete description ofthe structure and use of illustrative embodiments. Although certainembodiments have been described above with a certain degree ofparticularity, or with reference to one or more individual embodiments,those skilled in the art could make numerous alterations to thedisclosed embodiments without departing from the scope of thisinvention. As such, the various illustrative embodiments of the methodsand systems are not intended to be limited to the particular formsdisclosed. Rather, they include all modifications and alternativesfalling within the scope of the claims, and embodiments other than theone shown may include some or all of the features of the depictedembodiment. For example, elements may be omitted or combined as aunitary structure, and/or connections may be substituted. Further, whereappropriate, aspects of any of the examples described above may becombined with aspects of any of the other examples described to formfurther examples having comparable or different properties and/orfunctions, and addressing the same or different problems. Similarly, itwill be understood that the benefits and advantages described above mayrelate to one embodiment or may relate to several embodiments.

The claims are not intended to include, and should not be interpreted toinclude, means-plus- or step-plus-function limitations, unless such alimitation is explicitly recited in a given claim using the phrase(s)“means for” or “step for,” respectively.

REFERENCES

These references, to the extent that they provide exemplary proceduralor other details supplementary to those set forth herein, arespecifically incorporated herein by reference.

-   [1] Board W J, Caspers C, Street G M. A comparison of trans-tibial    amputee suction and vacuum socket conditions. Prosthetics and    Orthotics International. 2001; 25: 202-209.-   [2] Joan E. Sanders J E, Harrison D S, Allyn K J, and Myers T R,    Clinical Utility of In-Socket Residual Limb Volume Change    Measurement: Case Study Results Prosthetics and Orthotics    International 2009; 33: 378-390.-   [3] Convery P, and Buis A W. Conventional patellar-tendon-bearing    (PTB) socket/stump interface dynamic pressure distributions recorded    during the prosthetic stance phase of gait of a trans-tibial    amputee, Prosthetics and Orthotics International 1998; 22(3):193-8.-   [4] Hagberg K. and Branemark R., Consequences of non-vascular trans    femoral amputation: a survey of quality of life, prosthetic use and    problems. Prosthetics and Orthotics International 2001 December;    25(3):186-94.

The invention claimed is:
 1. An apparatus comprising: a flexible firstlayer comprising a substantially flat first portion and a plurality ofsecond portions each protruding away from the first portion to define achamber, a majority of which is surrounded by a boundary lying on thefirst portion; a flexible second layer that is substantially flat; wherethe first layer comprises a plurality of coupling members protrudingfrom the first portion opposite the second portions, the plurality ofcoupling members embedded in the second layer; where the first layer issealed in fixed relation to the second layer along the boundaries todefine a plurality of cells between the first layer and the second layerin the chambers and such that the first layer has a surface overlyingthe cells; and where the apparatus is configured to be coupled to afluid source such that the fluid source can deliver fluid to varyinternal pressures of the plurality of cells.
 2. The apparatus of claim1, where at least a portion of the surface is smooth such that cellsunderlying the smooth portion of the surface are configured to deflectthe smooth portion of the surface outwardly in at least a lateral and anaxial direction under an increased internal pressure of the cellsunderlying the smooth portion of the surface.
 3. The apparatus of claim1, where at least a portion of the surface is corrugated such that cellsunderlying the corrugated portion of the surface are configured todeflect the corrugated portion of the surface outwardly in asubstantially axial direction under an increased internal pressure ofthe cells underlying the corrugated portion of the surface.
 4. Theapparatus of claim 1, where the apparatus is configured such that aninternal pressure in at least one of the plurality of cells can bevaried independently of an internal pressure in another one of theplurality of cells.
 5. The apparatus of claim 1, where at least one ofthe plurality of cells has a transverse dimension that is different thana corresponding transverse dimension of another one of the plurality ofcells.
 6. The apparatus of claim 5, where at least some of the pluralityof cells sequentially decrease in size along at least one transversedirection of the flexible layers.
 7. The apparatus of claim 1, furthercomprising a plurality of sensors coupled to the apparatus andconfigured to detect one or more physical characteristics.
 8. Theapparatus of claim 7, where at least some of the sensors are configuredto detect at least one parameter selected from the group consisting of:pressure, shear force, temperature, and pH.
 9. The apparatus of claim 7,further comprising a processor configured to control the fluid source toadjust the internal pressure in the plurality of cells at least partlybased on data detected by the sensors.
 10. The apparatus of claim 1,further comprising: a memory configured to store pressure patterns; anda processor in communication with the memory and configured to controlthe fluid source to adjust the internal pressure in the plurality ofcells at least partly based on the pressure patterns.
 11. The apparatusof claim 1, where the apparatus is configured to be coupled to a bed ora seat.
 12. An apparatus comprising: a flexible first layer comprising afirst side that is substantially flat and a second side having asubstantially flat first portion and a plurality of second portions eachprotruding inward toward the first side to define a recess, a majorityof which is surrounded by a boundary lying on the first portion; aflexible second layer; where the first layer comprises a plurality ofcoupling members protruding from the first portion opposite the secondportions, the plurality of coupling members embedded in the secondlayer; where the first layer is sealed in fixed relation to the secondlayer along the boundaries to define a plurality of cells between thefirst layer and the second layer in the recesses and such that a surfaceof either the first layer or the second layer overlies the cells; andwhere the apparatus is configured to be coupled to a fluid source suchthat the fluid source can deliver fluid to vary internal pressures ofthe plurality of cells.
 13. The apparatus of claim 12, where a surfaceof the first layer overlies at least some of the plurality of cells anda surface of the second layer overlies at least some of the plurality ofcells.
 14. An apparatus comprising: a flexible first layer comprising asubstantially flat first portion and a plurality of second portions eachprotruding away from the first portion to define a chamber, a majorityof which is surrounded by a boundary lying on the first portion; aflexible second layer that is substantially flat; where the first layeris sealed in fixed relation to the second layer along the boundaries todefine a plurality of cells between the first layer and the second layerin the chambers and such that the first layer has a surface overlyingthe cells; where the apparatus is configured to be coupled to a fluidsource such that the fluid source can deliver fluid to vary internalpressures of the plurality of cells; and where the apparatus isconfigured such that a maximum displacement of the surface overlying atleast one of cells is between 2% and 15% of a transverse dimension ofthe cell for each pound per square inch (psi) increase in internalpressure between 1 psi and 5 psi.
 15. An apparatus comprising: aflexible first layer comprising a substantially flat first portion and aplurality of second portions each protruding away from the first portionto define a chamber, a majority of which is surrounded by a boundarylying on the first portion; a flexible second layer that issubstantially flat; where the first layer is sealed in fixed relation tothe second layer along the boundaries to define a plurality of cellsbetween the first layer and the second layer in the chambers and suchthat the first layer has a surface overlying the cells; and a fluidsource configured to be coupled to the layers and to deliver fluid tovary internal pressures in the plurality of cells.
 16. An apparatuscomprising: a flexible first layer comprising a substantially flat firstportion and a plurality of second portions each protruding away from thefirst portion to define a chamber, a majority of which is surrounded bya boundary lying on the first portion; a flexible second layer that issubstantially flat; where the first layer is sealed in fixed relation tothe second layer along the boundaries to define a plurality of cellsbetween the first layer and the second layer in the chambers and suchthat the first layer has a surface overlying the cells; where theapparatus is configured to be coupled to a fluid source such that thefluid source can deliver fluid to vary internal pressures of theplurality of cells; and where the apparatus is configured to be coupledto at least one item selected from the group consisting of: a prosthesissocket, a helmet, seat cushion, bed, mattress, pillow, and a prostheticlimb.
 17. A manipulator comprising: at least two opposing graspingmembers configured to move relative to one another to grasp an object;and an apparatus disposed on at least one of the grasping members suchthat the apparatus will contact an object grasped between the graspingmembers, the apparatus comprising: a flexible first layer comprising asubstantially flat first portion and a plurality of second portions eachprotruding away from the first portion to define a chamber, a majorityof which is surrounded by a boundary lying on the first portion; aflexible second layer that is substantially flat; where the first layeris sealed in fixed relation to the second layer along the boundaries todefine a plurality of cells between the first layer and the second layerin the chambers and such that the first layer has a surface overlyingthe cells; and where the apparatus is configured to be coupled to afluid source such that the fluid source can deliver fluid to varyinternal pressures of the plurality of cells.
 18. The manipulator ofclaim 17, further comprising a second apparatus, the second apparatuscomprising: a flexible first layer comprising a substantially flat firstportion and a plurality of second portions each protruding away from thefirst portion to define a chamber, a majority of which is surrounded bya boundary lying on the first portion; a flexible second layer that issubstantially flat; where the first layer is sealed in fixed relation tothe second layer along the boundaries to define a plurality of cellsbetween the first layer and the second layer in the chambers and suchthat the first layer has a surface overlying the cells; and where thesecond apparatus is configured to be coupled to a fluid source such thatthe fluid source can deliver fluid to vary internal pressures of theplurality of cells.
 19. A system comprising: robotic gripper orprosthetic, where the robot gripper or prosthetic comprises amanipulator, the manipulator comprising: at least two opposing graspingmembers configured to move relative to one another to grasp an object;and an apparatus disposed on at least one of the grasping members suchthat the apparatus will contact an object grasped between the graspingmembers, the apparatus comprising: a flexible first layer comprising asubstantially flat first portion and a plurality of second portions eachprotruding away from the first portion to define a chamber, a majorityof which is surrounded by a boundary lying on the first portion; aflexible second layer that is substantially flat; where the first layeris sealed in fixed relation to the second layer along the boundaries todefine a plurality of cells between the first layer and the second layerin the chambers and such that the first layer has a surface overlyingthe cells; and where the apparatus is configured to be coupled to afluid source such that the fluid source can deliver fluid to varyinternal pressures of the plurality of cells.